Retractable swimming pool cover



Feb. 6, 1962 E. s. KARAsu-:wlcz

RETRACTABLE SWIMMING POOL COVER '7, Sheets-Sheet 1 Filed Sept. 29, 1958mm mu m wm QSl 5w www 1% Wh. \\Nm. Qxl

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Feb. 6, 1962 E. s. KARAslEwlcz RETRACTABLE SWIMMING POOL COVER 7Sheets-Sheet 2 Filed Sept. 29, 1958 IN VEN TOR.

Feb. 6, 1962 E. s. KARAslEwlcz RETRACTABLE swIMMING PooL COVER FiledSept. 29, 1958 '7 Sheets-Sheet 3 Feb. 6, 1962 E. s. KARAslEwIczRETRACTABLE SWIMMING POOL COVER 7 Sheets-Sheet 4 Filed Sept. 29, 1958INVENTOR.

.y gsm 37 JJM# 25 60 .5.9 j

Feb. 6, 1962 E. s. KARAslEwlcz RETRACTABLE SWIMMING Pool. COVER 7Sheets-Sheet 5 Filed Sept. 29, 1958 Feb. 6, 1962 E. s. KARAslEwlczRETRAOTABLE SWIMMING POOL COVER '7 Sheets-Sheet 6 Filed Sept. 29, 1958Feb. 6, 1962 E. s. KARAslEwlcz 3,019,450

RETRACTABLE SWIMMING POOL COVER Filed sept. 29. 1958 '7 Sheets-Sheet 7 IZz @j gli? 031 50 J ited The principal object of this invention is toprovide an improved safety cover for a swimming pool, which may beadvanced over the water in the pool to prevent persons, especiallychildren, from falling into the water when the pool is not in use or isunattended, and which may be retracted from over the water in the pooland hidden from sight when access to the pool is desired. The safetycover is also useful in decreasing the amount of debris that may tend tofall into the pool.

In accordance with this invention the safety cover includes a ilexiblescreen which is adapted to extend horizontally over the water in thepool, and it is provided with aV plurality of spaced transverse supportswhich are movably received in and supported by guide channels whichextend along each side of the pool. A rotatable roll and rotatable cabledrum means are located at one end of the pool. One end of the screen isconnected, as by means of a plurality of cables or the like, to theroll, and the other end of the screen is connected by cable means to thecable drum means, preferably, there .being two cable drums and twocables which extend along the sides of the pool. Driving means areprovided for the roll and the cable drum means for rotating the same inopposite directions to wind the screen upon tie roll to pull and retractthe screen from over the water in the pool, and to wind the cable meanson the cable drum means to pull and advance the screen over the water inthe pool.

As the screen is so retracted and advanced, the number or" turns of thescreen on the roll and the number of turns of the cable means on thecable drum means will continuously vary, and since the screen is pulledfrom one end andthe other as it is so retracted and advanced, thedriving means for the roll and the cable drum means are so arranged, inaccordance with this invention,that the roll .and cable drum means maybe rotated at respectively dilerent speeds to compensate for thesevariations in said number of turns so that the screen may be freelyretracted and advanced without binding and setting up stresses therein.Towards thisend, the cable dmm means is permitted to rotatesubstantially freely in the unwinding direction as the roll is beingrotated in the winding direction to roll the screen thereon toretractthe screen, and the roll is permitted to rotate substantially freely inthe unvw'nding direction as the cable drum means is being rotated in thewinding direction to wind the cable means thereon to advance the screen.

ln the preferred embodiment of this invention there is provided areversibly rotatable drive shaft which may be driven selectively inopposite directions by a reversible electric motor, Meansincluding aone-way driving connection between the shaft and the roll rotates theroll in the windingdirection, when the shaft is rotated in onedirection, to wind the screen on the roll and retract the screen fromover the water in the pool. Also, means including a one-way drivingconnection between the shaft and the cable drum means rotates the cabledrum means in the winding direction, when the shaft is rotated in theopposite direction, to wind the cable means on the cable drum means toadvance the screen over the water in the pool. One of said one-waydriving connections, such as the one for the roll, ispreferably apositive driving connection, while the other of said one-.Way drivingconnections, such as the one for thecable drumimeans,

idfid Patented Feb. 6, ldt? is preferably a friction or clutch typedriving connection.

The cables for advancing the screen extend over pulleys at the oppositeend of the pool and preferably extend through guide tubes arranged alongeach side of the pool. These cables are preferably adjustably secured tothe cable drums. The plurality of cables which connect the screen to theroll are also preferably adjustable. By such adjustable means the screenmay be properly and accurately positioned.

The flexible screen preferably consists of a plurality of transverselyarranged wire helices which are pivotally hinged together throughouttheir lengths. This provides for maximum flexibility lengthwise of the'screen` and at the same time provides for maximum rigidity crosswise ofthe screen where sag must be eliminated. The plurality of spaced aparttransverse supports, which are movably received in the guide channelsand which guide and support the screen against sag, extend through ce1'-tain of transversely arranged wire helices and are preferably anchoredthereto to prevent relative movement therebetween.

The guide channels which extend along the :sides of the pool have, incross-sectional conguration, a vertical leg, a pair of horizontal legsand a pair of spaced apart vertical legs extending toward each other, asubstantially C-shaped cross-sectional configuration; The endsof thesupports of the screen carry fittings which extend into the guidechannels. Each tting includes a pair of hori- Zontal rollers whichengage the insides of the pair of spaced apart vertical legs of theguide channels. Each fitting also preferably includes a pair ofverticalr rollers which engage the facing edges of the pair of spacedapart vertical legs of the guide channels. These fittings effectivelymovably support the supports in the guide channels, minimize sagging ofthe screen and prevent twisting of the supports.

The guide channels are preferably embedded in the side walls of the pooland also embedded in the side walls below each guide channel is a cableguide pipe or tube for accommodating the cables which advance the coverover the water in the pool. Pipes are connected at intervals between theguide channels and the guide pipes or tubes soas to convey overdowentering-the guide channels into the guide pipes or tubes which slantdownwardly to discharge the overflow water to a convenient outlet.

A braking-arrangement is also preferably provided for the screen roll toprevent too rapid free rotation of the screen roll in the unwindingdirection as the cover is being advanced over the Water in the pool. Theswimming pool is also preferably provided with guide rollers where theretractable cover enters over the pool so as to compensate for sag andprevent scraping as the cover is being advanced or retracted.

These various features, and other features which will? be describedhereafter, all structurally and functionally cooperate with each otherto provide a new and improved retractable swimming pool cover which issimple and rugged in constructionwhich is `foolproof in operation, andwhich may be readily and inexpensively manufactured and installed. Y

Further objects and advantages of this invention will become apparent tothose skilled in the art upon reference to the accompanyingspecification, claims and drawings in which:

FIG. 1 is a vertical sectional View through the swimming pool with theretractable swimming pool: cover` shown extended over the water in thepool.

FIG. 2 isa vertical sectional view through the swimming pool cover takensubstantially along the line 2--2 ofFIG. l.

FIG. 3.- is a perspective view of the swimming ,pool` 3 cover showingthe mechanisms for retracting and advancing the same.

FIG. 4 is an enlarged vertical View of the right hand portion of FIG. land taken substantially along the line 4 4 of FIG. 5 and showing theoperating mechanisms for the retractable cover.

FIG. 5 is a horizontal sectional View taken substantially along the line5 5 of FIG. 1.

FIG. 6 is an enlarged vertical sectional view of a portion of FIG. 4 andtaken substantially along the line 6 6 of FIG. 5.

FIG. 7 is a perspective View of a portion of the leading edge of theretractable cover.

FIG. 8 is a Vertical sectional view taken substantially along the line 88 of FIG. 6.

FIG. 9 is a partial plan view of a portion of the leading edge of theretractable cover taken substantially along the line 9 9 of FIG. 7.

FIG. 10 is a perspective view of a portion of the trailing edge of theretractable cover. p

FIG. 11 is a vertical sectional view taken substantially along the line11-11 of FIG. 6.

FIG. 12 is a vertical sectional view taken substantially along the line12-12 of FIG. 1l.

FIG. 13 is a vertical sectional view of the retractable cover takensubstantially along the line 13 13 of FIG. 7.

FIG. 14 is a plan view, with parts broken away, of the retractable coverillustrated in FIG. 13.

FIG. 15 is a sectional View through the cable drum means for advancingthe retractable cover and taken substantially along the line 1.5 15 ofFIG. 5.

FIG. 16 is a sectional view through the cable drum means and takensubstantially along the line 16 16 of FIG. 15.

FIG. 17 is a vertical sectional View, with parts broken away, throughthe roll upon which the retractable cover is rolled.

FIG. 18 is a vertical sectional view taken substantially along the line1% 18 of FIG. 17.

FIG. 19 is a vertical sectional view taken substantially along the line19 19 of FIG. 18.

FIG. 2O is a plan View partly in section of the guide pulleys for thecables which advance the retractable cover.

FIG. 21 is an elevational view of the guide pulleys illustrated in FIG.20.

Referring first to FIGS. l, 2, 4 and 5, a swimming pool is generallydesignated at 10 and it includes a bottom wall 11, end walls 12 and 13and side walls 1d. The bottom Wall 11 is contoured as desired andincludes a drain outlet 15. The tops of the end walls 12 and 13 and theside walls 14 are provided with a suitable coping 16. The end Wall 13terminates short of the coping 16, there being provided a suitable beamstructure 17 for supporting the coping 16 above the vend Wall 13. Thereis thus provided an opening between the top of the end Wall 13 and thecoping 16 and beam structure 17 through which the cover for the swimmingpool may be retracted and advanced over the Water in the pool. The wallsof the pool may be suitably tiled if this is desired. Adjacent the endwall 13 of the pool 10 is a pit having a bottom wall 18, end walls 19and 20 and side walls 21. The pit is provided with supports 22 and 23for supporting the mechanisms which advance and retract the swimmingpool cover. The tops of the walls of the pit are provided with supports24 for supporting a suitable cover 25 for covering the pit.

As shown in FIGS. 1, 2, 4, 5, 6, 8 and 11, a guide channel 2S extendsalong each side of the swimming pool, this guide channel being embeddedin the side walls 14 of the swimming pool. The guide channels aresubstantially C-shaped in cross-sectional configuration and have avertical leg 29, upper and lower horzontal legs 30 and substantiallyvertical legs 31 extending toward veach other. Preferably, these legs 31diverge outwardly as they extend toward each other. The guide channelsmay be securelyanchored in the side walls 14 by means of anchoringfittings 32. The far ends of the guide channels 28 terminate in cavities39 in the end Wall 12 of the swimming pool. The near ends of the guidechannels 28 extend into the pit at the near end of the swimming pool,the guide channels 2S extending dovvardly as they enter the pit. Thehorizontal legs 30 of the guide channels 28 and the legs 31 dependingtherefrom diverge as they enter the pit as illustrated at 33 and 34 inFIGS. 4 and 6. Guide strips 35 extend from the ends 34 of the guidechannels 28 to the iioor 18 of the pit, they being secured to the floor13 by suitable means indicated at 36.

Also extendincr along each side of the swimming pool is a cable guidepipe 3%, the pipes 3S being embedded' in the side walls 14 of theswimming pool. The far ends of these cable guides 3S communicate withthe cavity in the end Wall 12 of the swimming pool and the near endscommunicate with the interior of the pit. The cable guide pipes 33 slantdownwardly toward the pit 18 and the cable guide pipes 38 are connectedat intervals by pipes 41 communicating with the interior of the channelguides 23. Thus, any overflow of water in the swimming pool which entersthe channel guides 28 is directed through the pipes 41 into the cableguide pipes 33, the overow water emptying into the pit 18 where it issuitably conveyed away by drains in the bottom wall 1S of the pit.

Ihe cavities 39 in the end wall 12 are provided with suitable pulleys4t?. A pair of guide pulleys 42 and 43 are carried by the wall 19 of thepit adjacent to the point where the cable guide pipes 3S enter the pit,the construction of the guide pulleys being illustrated in more detailin FIGS. 20 and 21. The guide pulleys 4Z and 43 are rotatably carried bypins 44 and 45, respectively, which in turn are carried by plates 46secured to a plate 47 Which in turn is attached to the Wall 19 of thepit.

The retractable cover for the swimming pool includes a screen 50 whichis made up of a plurality of Wire helices 51 and 52 which extendtransversely across the pool and Which are pivotally connected togetherby transverse wires 53, as shown more clearly in FIGS. 7 and 9 to 14.This screen 59, so formed, is extremely flexible in the lengthwisedirection but is relatively rigid in the crosswise direction so as tominimize sag. The wire helices 51 and S2 are preferably formed fromaluminum or other light Weight metal so as to keep the weight of thescreen as low as possible. The aluminum wire helices may be anodize indesired colors so as to enhance the appearance of the cover. Thescreen'Stl is transversely supported by a plurality of supports 54,these supports extending through the Wire helices 52. 'Ille number ofthe transverse supports 54 utilized depends upon the dimensions of theswimming pool to be covered. The Wire helices S1 which do not containthe transverse supports 54 are preferably flattened so as to have lessthickness than the wire helices 52 through which the supports 54 extend.The supports 54 are preferably made from tubes of light Weight metalsuch as aluminum or the like and they are secured to the Wire helices 52by means of U-bolts 55 as illustrated in FIGS. 11 and 12. The U-bolts 55operate to prevent relative displacement and movement of the supports S4and the wire helices 52.

Each end of each tubular support 54 is provided with a fitting 57, thetitting S7 being received in the end of the tubular support 54 and beingheld in place therein by bolts 58. Each fitting 57 carries a verticalpin 59 upon which are rotatably mounted a pair of horizontal rollers 60,the rollers 60 engaging the sides of the depending legs 31 of the guidechannels 2S. Each fitting also carries a pair of horizontal pins 61which in turn rotatably carries a pair of'vertically arranged rollers 62which engage the facing edges of the legs 31 of the channel guide 28.The rollers 6) and 62 operate in conjunction With the guide channel 23to movably support and guide the supports of the screen Sil. Thehorizontal rollers titl absorb the horizontal stresses caused by theweight of the screen on the supports 54tand greatly minimize the amountof sag in the screen il. The vertical rollers 62, operate principally toguide the supports 54E- and to prevent turning thereof so as to maintainthe rollers in proper position with respect to the channel guides 2?.The various supports 54;- are preferably tied together by means oflongitudinally extending cables d3 secured by clamps ed so as tomaintain relatively iixed spacing between the supports 54 and tocompensate considerably for the resiliency of the screen Sil.

A channel o7, as illustrated more clearly in FlGS. 3, 1G and 14, issecured by spacers oand bolts 69 to the support forming the trailingedge of the retractable cover, that is the enge nearest to the pit. Thischannel 67 operates to reinforce this end support 54. The channel `67carries a plurality of lugs 7i), four lugs being shown for purposes ofillustration, the lugs 7@ each having a hole 71. The other end of thescreen, that is the leading end remote from the pit, is also providedwith a channel 72. The channel 72 is preferably serni-octagonal incross-sectional configuration so as to provide maxirum rigidity. Thechannel 72 is secured by spacers 73 and bolts M to the end support d,this construction being illustrated in more detail in FlGS. 3, 7, 9, 13and 14.

he vertical pins 59 which carry the rollers oil ofthe leading endsupport 5l!A are each provided with a yoke 75.

A plurality of cables 7b, as shown in FIGS. 3, l0, 13 and 14 extendthrough the holes '71 in the lugs 'itl on the channel o7 and they areadjustably secured together by turn buckles 79. These cables '7S extendto and are secured to lugs dit carried by a roll 81 arranged within thepit. As the roll 1 is rotated in a winding direction, the cables 73 pullthe screen 5d and wind the same on the roll 31 and, in this way, tl escreen Sil is retracted from over the water in the pool.

A pair of cables 53 are connected to the yokesv 7S carried by theleading edge of the screen Sil. These eabiesytla extend over the pulleyslil in the cavities 39 in the end wall l2 of the swimming pool andextend through the cable guide tubes 3iand over the guide pulleys 42 andto a pair ot cable drums 34 arranged within the pit. As the cable drums84 are rotated in a winding direction, the cables 83 operate to pull thescreen 50 and advance the same over the water in the pool. When thecable drums Sd are rotated in a winding direction to advance the screenover the pool, the screen roll 81 is allowed to rotate substantiallyfreely in order that the Screen may be advanced without stressing orbinding. Conversely, when the screen roll dl is rotated in a windingdirection to retract the screen from over the water in the pool, thecable drums 3d are allowed to rotate substantially freely so as toprevent stressing and binding as the screen is being retracted.

Referring now to FlGS. 3 to 5 and 17 to 19, the screen roll Sl isprovided with bearing niern'bersi for rotatably mounting the same upon ashaft 88` whichl in turn is rotatably mounted in bearings S9 carried bythe supports 2,2 in the pit. A sprocket wheel 9i? is secured to theshaft E@ and is connected by a chain 91 to a sprocket wheel 92 driven bya gear reducer 93 which in turn is driven by an electric motor grimounted on the support 23 in the pit, The electric motor 14 is areversible motor and when it is operated in one direction, the shaft fis rorated in one direction and when it is operated in the oppositedirection, the shaft di; is rotated in the opposite dil rection. As theshaft is thus rotated in one direction or the other, the screen isretracted from or advanced over the water in the swimming pool.

A ratchet whe-el 96 is secured to the shaft 8d and is rotated in onedirection or the other thereby. One ot the bearing members 87 of thescreen roll 31 has a pair of pawls 97 pivotally secured thereto by pins98. Springs @l 9i? extending between the pawls 97 and the bearing member87 operate to resiliently engage the pawls 97 with the ratchet wheel 96.Whenf the shaft 8S, as illustrated in FIGS. 3, t and 18 is rotated in aclockwise direction, the ratchet wheel 95 which is positively engagedIby the pawls 97, operates to rotate the screen roll S1 in a clockwiseor winding direction to roll the screen 5i) upon the screen roll 81.When, however, the shaft 88 and the ratchet wheel 96 are rotated in acounterclockwise direction, the ratchet wheel 96 slips past the springpressed pawls 97 and does not impart any rotation to the screen roll 81.When this occurs, the` screen roll 81 is allowed to rotate substantiallyfreely in the unwinding direction so long as its rotation in thatdirection does not exceed the speed of rotation of the shaft SS in thecounter-clockwise direction. A positive one way driving connection is,therefore, provided between the shaft @d and the screen roll 81, itoperating to positively roll the screen on the roll S1 when operating ina winding direction but permitting substantially free rotation of theroll in the unwinding direction when unwinding of the screen from theroll is desired.

Referring more particularly to FIGS. 3, 4, 5, 15 and 16, the pair ofcable drums @d for winding the cables are rotatably mounted onstationary shafts ibi which are carried by brackets 102 secured. tosupports 193 which in turn are secured to the wall 2i? of the pit. Theshafts lill are held against rotation by the brackets 1m. The cables 833extend through holes `lila in flanges on the cable drurns Siand extendover pins 1635 on the cable drums and are adjustably clamped in positionby means of clamps 166 secured to the cable drums. 11n this way, thecables 83 are adjustably secured to the cable drums d4.

Each rotatable cable drum is provided with a cylindrical extension 198and a ratchet wheel 199 is rotatably mounted on the cylindricalextension 11%8 by a suitable bearing liti. Thus, the ratchet wheel 109is rotatably mounted with respect to the cable drum l and the cable rum@4- is rotatably mounted on the stationary shaft lill. A sprocket wheel111 having a. cylindrical extension 112 is rotatably mounted ontlrcstationary shaft dbd by a bearing 113. The cylindrical extension 112 ofthe sprocket wheel 111 is coaxial with the cylindrical extension 138 ofthe cable drum 84, these two cylindrical extensions 112 and ltS beingrotatable with respect to each other. A helical spring 11:4 is arrangedaround the cylindrical extensions 1F19 and 198 andit has one end 115extending into a hole 116 in the rotatably mounted sprocket wheel 1429.The other end of the coil spring 114, as indicated at 117 in FIG. 15, isforme-d to press against the cylindrical extension 112 of the sprocketwheel` 1111. As the sprocket wheel 111 and its cylindrical extension1:12 are rotated in a counter-clockwise. direction, as illustrated inFiG. 15, the coil spring 114 winds upon the cylindrical extensions 112and 19S to couple these extensions together so as to rotate thecylindrical extension Hi8` and the cable drum 34 in a counter-clockwisedirection. When this occurs, the ratchet wheel lilik-rotates with thecable drum 84, it being rotated by the spring 114. When, however, thesprocket wheel 111. and its cylindrical extension 1112 are rotated in aclockwise direction and the ratchet wheel 109 is held against rotationin that direction, the coil spring 114 unwinds so as to disengage thecoupling between the cylindrical extensions 112 and 193 so that thecylindrical extension 168 and the cable drum 84 are allowed to freelyrotate. The coupling for the cable drums is, therefore; a friction orclutch type of coupling.

The sprocket wheels 111 of the cable drum means are connected by chains118 to sprocket wheels 119 secured to the shaft Sil. Thus, as theshaft'SS is rotated in a counterclockwise direction so as to free thescreen roll`31 for rotation in the unwinding` direction, the cable drums84- are driven in counter-clockwise or winding direction to advance thescreen over the water in the pool. When the 7 shaft 88 is rotated in aclockwise direction, the cable drums 84 are freed Yfor substantiallyfree rotation in the unwinding direction and the screen roll S1 isrotated in the winding direction to retract the screen from over thewater in the pool.

Each support 103 for the cable drum means is provided with a pair ofbrackets 124B upon which is mounted a solenoid 121. The armature of thesolenoid 121 is connected at 122 to one end of a link 123 which isconnected at its other end at 124 to a pawl 12S pivoted to the support126 at 126. The pawl 125 is provided with a shoulder 127 which isadapted to engage the ratchet Wheel 169. A spring 128 connected betweenthe link 123 and the bracket 120 normally disengages the pawl 127 fromthe ratchet wheel M19 but when the solenoid 121 is energized, theshoulder 127 of the pawl is brought into engagement with the ratchetwheel 109. When the reversible electric motor 94 is energized to locatethe screen roll S1 in the winding direction to retract the screen, thesolenoids 121 are energized to cause the pawls 1215 to engage theratchet wheels 109 soas to insure the breaking of the coupling betweenthe cylindrical extensions 112 and 1% so as to allow the cable drums 84to rotate freely during the retracting operation.

As shown more clearly in FIGS. 4, 6 and 8, a bracket 130 is secured tothe top of the wall 19 of the pit and the bracket 130 carries a limitswitch 131 which is operated by a pivoted lever 132 having a roller 133.The roller 133 engages the underside of the screen Sil and is helddepressed by the screen. When the roller 133 is depressed by the screen,the limit switch 131 is closed. When the screen is completely advancedover the water in the pool to a point beyond the roller 133, the rollerswings upwardly to open the limit switch. Likewise, when the screen Si)is retracted from over the water in the pool to a point beyond theroller 133, it also swings upwardly to Open the limit switch 131. Thelimit switch 131 is included in the electrical control circuits for thereversible electric motor and when the switch is opened as a result ofthe screen being fully advanced or retracted, the operation of theelectric motor 94 is automatically stopped.

Because there is some tendency for the retractable cover for theswimming pool to sag, the tops of the walls 19 and 13 are provided witha plurality of supporting rollers 135, 136 and 137 for supporting andguiding the screen as it passes over the tops of the walls 19 and 13below the coping 16 and beam structure 17. These rollers in sosupporting the screen, as it is moving, allows the screen to passthrough the relatively narrow opening below the coping 16.

As the screen is unrolled from the screen roll 81, the iittings at theends of the supports thereof are guided into the guide channels 28 bythe guide strips 35 and the ared mouths 33 and 34 of the guide channels28 and, as a result, fool proof operation without binding is broughtabout. Since the screen roll S1 is freed for rotation as the screen isbeing advanced over the water in the pool, braking mechanisms areprovided to prevent the screen from unrolling too rapidly due to inertiaof the rotating mass. The braking mechanisms are arranged in the pitadjacent the screen roll and each braking mechanism, as illustrated moreclearly in FIGS, 4 and 5, includes a base 140 and uprights 141 and 142.An arm 143 is pivoted intermediate its ends at 144 to the upright 142.The outer end of the arm 143 carries a roller 14S which engages thescreen 50 on the screen roll 81 and which is urged into engagement withthe screen by springs 146 extending between the other end of the arm 143and the upright 141. The spring pressed roll 145 places suiiicient dragupon the rolled screen as it is being unrolled from the screen roll 31to prevent too rapid unrolling thereof which might cause piling up ofthe screen on the floor of the pit.

The various electrical controls for the electric motor 94 and thesolenoids 121 of the cable drum means may be located in a control box150 arranged within the pit. The

controls in the control box are controlled by the limit switch 131 andby suitable manually operated switches for controlling the advancing andretracting of the screen. The control circuits are conventional and arenot illustrated herein.

I claim as my invention:

l. A retractable cover for a swimming pool comprising a guide channelextending along each side of the pool, a iiexible screen adapted toextend horizontally over the water in the pool and having spacedtransverse supports movably received in and supported by the guidechannels, a rotatable roll and rotatable cable drum means located at oneend of the pool, means connecting one end of the screen to the roll,cable means connecting the other end of the screen to the cable drummeans, a reversibly rotatable drive shaft, means including a onewaydriving connection between the shaft and the roll for rotating the rollin the winding direction when the shaft is rotated in one direction towind the screen on the roll and retract the screen from over the waterin the pool, and means including a one-way driving connection betweenthe shaft and the cable drum means for rotating the cable drum means inthe winding direction when the shaft is rotated in the oppositedirection to wind the cable means on the cable drum means and advancethe screen over the water in the pool.

2. A retractable cover for a swimming pool comprising a guide channelextending along each side of the pool, a iiexible screen adapted toextend horizontally over the Water in the pool. and having spacedtransverse supports movably received in and supported by the guidechannels, a rotatable roll and rotatable cable drum means located at oneend of the pool, means connecting one end of the screen to the roll,cable means connecting the other end of the screen to the cable drummeans, a reversibly rotatable drive shaft, means including a one-waydriving connection between the shaft and the roll for rotating the rollin the winding direction when the shaft is rotated in one direction towind the screen on the roll and retract the screen from over the waterin the pool, and means including a one-way driving connection betweenthe shaftrand the cable drum means for rotating the cable drum means inthe winding direction when the shaft is rotated in the oppositedirection to wind the cable means on the cable drum means and advancethe screen over the water in the pool, one of said one-way drivingconnections being a positive driving connection, and the other of saidone-way driving connections being a friction driving connection.

3. A retractable cover for a swimming pool comprising a guide channelextending along each side of the pool, a ilexible screen adapted toextend horizontally over the Water in the pool and having spacedtransverse supports movably received in and supported by the guidechannels, a rotatable roll and a pair of cable drums located at one endof the pool, a pair of pulleys located at the other end of the pool,cables connecting one end of the screen to the roll, a pair of cablesextending over the pair of pulleys and connecting the other end of thescreen to the pair of cable drums, a reversibly rotatable drive shaft,means including a one way drive connection between the shaft and theroll for rotating the roll in the Winding direction when the shaft isrotated in one direction to wind the screen on the roll to pull thescreen from over the water in the pool, and means including one-waydrive connections between the shaft and the pair of cable drums forrotating the cable drums in the winding direction when the shaft isrotated in the opposite direction to wind the pair of cables on thecable drums and pull the screen over the water in the pool.

4. A retractable cover for a swimming pool comprising a guide channelextending along each side of the pool, a flexible screen adapted toextend horizontally over the water in the pool and consisting of aplurality of transversely arranged wires and a plurality of transverselyarranged wire helices pivotally hinged together throughout their lengthsby the Wires, and a plurality of spaced transverse supports extendingthrough certain of the transversely arranged wire helices and with theends of each of them movably received in and supported by the guidechannels.

5. A retractable cover for a swimming pool comprising a guide channelextending along each side of the pool, a liexible screen adapted toextend horizontally over the water in the pool and consisting of aplurality of transversely arranged wires and a plurality of transverselyarranged Wire helices pivotally hinged together throughout their lengthsby the wires, a plurality of spaced transverse supports extendingthrough certain of the transversely arranged wire helices and with theends of each of them movably received in and supported by the guidechannels, and means for anchoring the transverse supports to theirrespective transversely arranged wire helices.

6. A retractable cover for a swimming pool comprising a guide channelextending along each side of the pool, a ilexible screen adapted toextend horizontally over the water in the pool and having spacedtransverse supports movably received in and supported by the guidechannels, a rotatable roll and rotatable cable drum means located at oneend of the pool, means connecting one end of the screen to the roll,cable means connecting the other end of the screen to the cable drummeans, a reversibly rotatable drive shaft, means for connecting the rollto the shaft when the shaft is rotated in one direction for rotating theroll only in the winding direction to wind the screen on the roll andpull the screen from over the water in the pool, and means forconnecting the cable drum means to the shaft when the shaft is rotatedin the opposite direction only to wind the cable means on the cable drummeans and pull the screen over the water in the pool.

7. A retractable cover for a swimming pool comprising a guide channelextending along each side of the pool, a tiexible screen adapted toextend horizontally over the water in the pool and having spacedtransverse supports movably received in and supported by the guidechannels, a rotatable roll and a pair of cable drums located at one endof the pool, -a pair of pulleys located at the other end of the pool,cables connecting one end of the screen to the roll, a pair of cablesextending over the pair of pulleys and connecting the other end of thescreen to the pair of cable drums, a reversibly' rotatable drive shaft,means including a one way drive connection between the shaft and theroll for rotating the roll in the winding direction when the shaft isrotated in one direction to wind the screen on the roll to pull thescreen from over the water in the pool, and means including one waydrive connections between the shaft and the pair of cable drums forrotating the cable drums in the Winding direction when the shaft isrotated in the opposite direction to wind the pair of cables on thecable drums and pull the screen over the water in the pool, and meansfor retarding rotation of the roll in the unwinding direction.

8. ln a retractable cover for a swimming pool, having a tiexible screenadapted to extend horizontally over the water in the pool, and means foradvancing and retracting the screen over the water in the pool, saidmeans comprising a drum for moving the screen, a cylindrical extensionon the drum, a power driven cylindrical extension concentric with thecylindrical extension on the drum, means for rotating the power drivencylindrical extension in one direction or the opposite direction, ahelical spring encompassing the cylindrical extension on the drum andthe power driven cylindrical extension for coupling the cylindricalextension on the drum to the power driven cylindrical extension when thepower driven cylindrical extension is rotated in one direction forrotating the drum in said one direction and for decoupling thecylindrical extension of the drum from the power driven cylindricalextension when the power driven cylindrical extension is rotated in theopposite direction to allow substantially free rotation of thecylindrical extension of the drum in said opposite direction,

9. In a retractable cover for a swimming pool, having a flexible screenadapted to extend horizontally over the water in the pool, and means foradvancing and retracting the screen over the Water in the pool, saidmeans comprising a drum for moving the screen, a cylindrical extensionon the drum, a power driven cylindrical extension concentric with thecylindrical extension on the drum, means for rotating the power drivencylindrical extension in one direction or the opposite direction, ahelical spring encompassing the cylindrical extension on the drum andthe power driven cylindrical extension for coupling the cylindricalextension on the drum to the power driven cylindrical extension when thepower driven cylindrical extension is rotated in one direction forrotating the drum in said one direction and for decoupling thecylindrical extension of the drum from the power driven cylindricalextension when the power driven cylindrical extension is rotated in theopposite direction to allow substantially free rotation of thecylindrical extension `of the drum in said opposite direction, arotatably mounted wheel connected to one end of the helical spring androtatable in said one direction when the power driven cylindricalextension is rotated in said one direction, and means for locking saidwheel against rotation in said opposite direction when the power drivencylindrical extension is rotated in said opposite direction to insurenncoupling of said cylindrical extension of the drum from the powerdriven cylindrical extension.

References Cited in the file of this patent UNITED STATES PATENTS1,461,026 Booraem July 10, 1923 1,670,094 Becker May 15, 1928 2,136,042Cornell et al. Nov. 8, 1938 2,754,899 Karobonik et al. July 17, 19562,756,438 Soberman July 3l, 1956 2,839,135 Anderson .lune 17, 19582,844,196 Jones July 22, 1958 2,898,607 McGuire Aug. 11, 1959 2,958,083Shock et al, Nov'. l, 1960 FOREGN PATENTS 139,330 Austria Nov. l0, 1834

